The invention relates to a device for girding an article with a strip of adhesive tape, whereof ends can adhere to one another, which device comprises:
a housing with a cavity for accommodating a supply roll of adhesive tape with: PA0 a star wheel rotatable with light friction having a number of spokes bounding identical, substantially radial recesses disposed at mutually equal angular distances, PA0 two mutually registered slits open on one side which are present in the front wall and the rear wall respectively of the housing and which together bound a channel wherethrough an article for girding has to be moved from the open side, PA0 wherein the adhesive tape is guided over the top part of the star wheel with the sticking side facing outward, PA0 wherein the star wheel is formed and positioned relative to the slits such that an article for girding engages onto the star wheel in a recess thereof adheringly carrying with it the first tape, the opening of which recess is situated in the region of the slits, whereby the star wheel is set into rotation so that in the recess the article is girded with adhesive tape with the progressive rotation of the star wheel, and PA0 wherein the cutting means are placed downstream in relation to the star wheel and comprise a tilt piece with an actuating part movable pivotally about a pivot axis toward and away from the channel, which tilt piece is urged by spring means to a rest position wherein the cutting knife is located at a distance from the channel and the actuating part is located in the region of the channel for actuation of the tilt piece by an article carried through the channel while severing the tape with which an article is girded. Such a device is known for instance as sealer for bags with food products. The invention has for its object to provide a device, the operation of which is substantially independent of the dimensions of a through-fed article. A derived object of the invention in this respect is to provide a device which is for instance suitable for sealing plastic waste bags and binding bunches of flowers.
means for guiding the tape; PA1 means for carrying an article at least along and against the adhesive side of the first tape; and PA1 cutting means actuable by a through-fed article for severing the tape after the article has passed over the said means,
A problem with known devices of the said type is that the positioning of the star wheel can be greatly dependent on the thickness of a through-fed article. During girding of an article the star wheel has to be positioned such that a following article can be introduced into the channel without disturbance for girding by the device.
In order to ensure this positioning under all conditions, which is essential for good, disturbance-free operation of the device, the device according to the invention is characterized by
a movable positioning arm, for instance arranged hingedly on the tilt piece which, in the position wherein the knife severs the tape, engages with its free end into a recess in the star wheel, whereby this star wheel is positioned such that another recess is situated in the region of the channel and is ready to receive an article for girding. This configuration has the additional advantage of requiring only very little space.
In preference the device has the feature that the free end of the positioning arm has a form adapted to the form of the recesses. This ensures a small contact pressure while retaining the desired disturbance-free operation.
A positive positioning is achieved with an embodiment which has the feature that when the tilt piece is moved out of the inactive position to the cutting position thereof the arm is carried to its positioning position in a recess of the star wheel by a stop present on the tilt piece.
In a preferred embodiment the device has the feature that the spring means comprise a draw spring connected on one side to the housing and on the other to the positioning arm in a zone located on the side of this positioning arm remote from the said free end. Two functions are here combined with one another, namely resetting of the tilt piece into its ready for operation position and the retraction of the positioning arm.
In order to press together as well as possible the adhering outer ends of the girding tape lying against each other the device can be characterized by a first resilient lip which presses in the region of the channel against the outer ends of the spokes of the star wheel. For this same purpose the device can be characterized by a deflection member which extends in the channel between the star wheel and the cutting means and which, during girding of an article, presses together with increased force the mutually facing adhering surfaces of the adhesive tape.
In order to make the longitudinal guiding of an article through the channel as good as possible, irrespective of its dimensions, the device can be characterized in a preferred embodiment by a strip extending in lengthwise direction of the channel with one side in that channel and resiliently loaded toward one of the longitudinal edges of the channel such that between the boundary of the channel and the said longitudinal edge a through-fed article is subjected to a pressing force on its zone girded by adhesive tape. The form of the active longitudinal edge of the strip is adapted to the form of the boundary of the channel located opposite. The strip forms with its longitudinal edge a slight impress in the handled article whereby a positive guiding is effected. Sideways sliding out of the article is hereby prevented. This sliding out in sideways direction is undesirable since the quality of the girding operation could thereby leave something to be desired.
This embodiment can have the particular feature that the strip is arranged hingedly on the input side of the channel.
The device can be embodied such that the strip is spring loaded by a second resilient lip.
This latter variant can have the characteristic that the first resilient lip and the second resilient lip are formed integrally. The said resilient lips can be of any suitable material, for instance spring steel.
In order to make the adhering action of the pressure-sensitive adhesive tape as strong as possible the device can display the feature that the tilt piece comprises a pushing part which is placed opposite the actuating part and which can exert a pushing force on the through-fed article during progressive tilting of the tilt piece.
As stated above, it is essential for good operation of the device that the star wheel can be positioned correctly by the positioning arm under all conditions, irrespective of the dimensions of a through-fed article. In this respect the invention preferably also has the feature that the ends of the spokes of the star wheel and the free end of the positioning arm are formed and co-act such that the said free end can enter a recess in any position of the star wheel while avoiding a dead point.
For manufacture of the device any suitable material can in principle be considered. It is recommended however to make use of a strong plastic which allows of processing by injection moulding. The device can have the particular feature that the device consists substantially of a strong plastic from the group to which ABS and polycarbonate belong.
The drawback to the said plastics is that they are relatively expensive, which could be a commercial obstacle in the case of simpler devices of the said type, for instance for consumer uses. It is therefore desirable to choose a material which is less expensive but which retains reasonable strength properties. In this respect the device can have the characteristic that the device consists substantially of polypropylene with a reinforcement of rockwool fibres. The combination of polypropylene with rockwool fibres has the great advantage of possessing substantially the same thermal properties as the above mentioned plastic ABS and of therefore allowing processing in the same injection moulds as ABS.
For the above stated applications such as sealing domestic refuse bags and binding of flowers it can be advantageous to provide the device with a hand-grip.